Christopher Hirst visits the heart of Kent to discover the dark secrets of the pickled walnut
For some of us, a small, knobbly, brown-black, oval nut is the apogee of pickles. Good all year round, it really comes into its own on Boxing Day when it plays a star role. Sliced into sour-sweet, tantalisingly flavoured discs, it superbly enhances the platter of sliced meats and pork pie that is infinitely preferable to the gruesome blowout of the previous day. I refer to the excellent pickled walnut. Pickling involves the baby nut within its dull green husk, which can be harvested for two or three months until mid-July.
As soon as the brown shell of the nut begins to form within the green husk, it’s hopeless. On 15 July, my wife and I acquired (‘pinched’ is the more accurate term), a couple of dozen green walnuts, which appeared perfect for pickling. Sadly, an experimental slice revealed the brown crescent indicating the formation of the walnut shell. Our haul went into the recycling bin.
Fortunately, we already had 1½ kilos of perfect baby nuts from Alexander Hunt, a genial 55-year-old who runs the market-leading Walnut Tree Company from his cottage in the leafy heart of Kent, The pickling process, which takes three months, results in a condiment adored by top British chefs such as Jeremy Lee of Quo Vadis In London’s Soho. ‘Pickled walnuts make up one of the great trinities of the kitchen: roast beef, horseradish and pickled walnuts,’ Jeremy enthused. ‘The spike of a fine horseradish, along with pickled walnut and a slice of roast beef is a remarkable dish that never fails to delight. Each elevates the other and requires no embellishment except maybe a posy of perfect watercress.’
If you haven’t already snapped up a few kilos of green walnuts for pickling, your best bet, according to Alexander, is to buy the pickled walnuts sold by the Fine Cheese Company of Bath. He described another leading brand as ‘very sharp and sour due to cheap vinegar. They’re far better made with wine vinegar.’
I love them, even the ‘sharp and sour’ ones denigrated by Alexander, but not everyone shares this passion. In the new ingredient guide River Cottage A-Z, the entry on the walnut does not seem to be an unmitigated plaudit for the pickled variety: ‘They are an acquired taste but some people seem to like them.’
As the green walnuts sit in their bath of brine for a couple of weeks, the liquid rapidly turns murky black. Alexander explained that even this has a commercial value: ‘We sell quite a lot to an Indian gent in Leeds as a dyestuff. They’re also used medically for use in a tincture for inflammatory conditions. The Turks love glacé walnuts.’ My wife vigorously confirmed Alexander’s warning, ‘Handling fresh wet walnuts, your hands go black as your hat.’
‘Yes, you really need to wear plastic gloves from the moment you touch a walnut,’ she said, sticking up a couple of very noir thumbs. ‘And that’s only from changing the brine.’
Slightly older nuts, when the husk splits open, are known as fresh wet walnuts. ‘The French love them with wine and cheese. They’re delicious and full of moisture but they don’t keep.’
The final stage of the walnut is when they reach the familiar hard nut that magically appear in the run-up to before Christmas. The distinctive ‘Snap!’ when they’re cracked is the result of kiln drying.
The Walnut Tree Company sells around a tonne (1,000 kilos) of green nuts for pickling each year, along with four to five tonnes of fresh wet nuts and the same quantity of dried nuts. They’re grown by Alexander’s partners in the Walnut Tree Company, Alan and Anne Olley, who pick 30 acres of cobnuts and 10 acres of walnuts at Potash Farm, St Mary’s Platt, near Sevenoaks.
Alexander says that demand for walnuts is on the rise. The reason is partly health-based. ‘They’re good brain food and lower cholesterol – just eat half a dozen and you’ll find it goes down. They’re also good for the immune system. Walnuts have the highest antioxidant activity of all nuts. They are brimming with vitamin E. Studies have shown that eating them can reduce the risk of a heart attack from between 15 and 51 per cent.’ But it also seems that the British palate is warming to the dry, subtle potency of the walnut.
Originating in central Asia, the walnut was introduced to Britain by the Romans as a useful form of nutrition. The Victorians put them on the menu as an accompaniment to vintage port. Walnuts became popular in Edwardian gardens due to the unexpected citrus smell released when the leaves are picked.
Selling around 8,000 cobnut and walnut trees per year, Alexander’s company is the only UK outfit that markets the nutty gamut from saplings to nut-based products, such as walnut oil. This is known as ‘plough to plate’ in the nut world. He advocates the flavour-packed walnut oil on avocados, but our favourite application is raw tuna. Cut a fillet into thin slices and sprinkle with walnut oil and soy sauce, it’s the tastiest and cheapest sashimi you can find.
The best way of ensuring a supply of walnuts, green, wet or dry, is to grow your own, ‘Walnuts need a bit of heat but we sell them as far north as the borders,’ said Alexander. ‘They’ll happily fruit in Berwick. The trees are virtually pest-free. They’re low maintenance and disease-free. You should plant walnut trees in November to February when they’re fully dormant. They costs £35-40 and you’ll get your first walnuts in two to three years. The biggest problem is squirrels.’ There are only about 200 acres of commercially grown walnuts in Britain. Most of the Christmas glut comes from California or China.
‘At Christmas, imported nuts cost £12-14 per kilo while our nuts are £10-12,’ said Alexander. ‘Probably we need to jack the price up a bit.’ Their acclimatisation to Britain was confirmed by a visit to the handsome arboretum in East Malling, which holds the national collection of 120 varieties. They include a type known as the East Down Claw Nut, brought to Kent by the Romans.
A walnut-rich meal made by Alexander’s near-neighbour Deborah Orm from Anne Olley’s book Cooking with Walnuts highlighted their excellence as an ingredient. In Alexander’s flower-decked garden, we ate dark, nutty brownies, cheese and walnut pinwheels (very tasty), venison with mushrooms and pickled walnuts, cidered chicken breasts, followed by walnut parfait roulade and walnut and chocolate tarts. It was transporting if slightly too generous for a hot day. Groaning ever so slightly, we make our way from this walnutty heaven with our treasure trove of baby nuts for future feasts.
For details of Alexander’s trees and walnut products: kentishcobnuts.com or walnuttrees.co.uk
for Anne Olley’s walnut recipes, visit breadandoysters.com/walnut-recipes/